Section forming mechanism



June 11, 1963 H. D. WARD, JR

SECTION FORMING MECHANISM 2 Sheets-Sheet 1 Filed May 20, 1960 June 11, 1963 H. D. WARD. JR

SECTION FORMING MECHANISM 2 Sheets-Sheet 2 Filed May 20, 1960 BY wfwi United States Patent 3,093,037 SECTION FORMING MECHANISM Henry D. Ward, Jr., Timouium, Md., assignor to Koppers Company, Inc., a corporation of Delaware Filed May 20, 1960, Ser. No. 30,678 8 Claims. (Cl. 93-582) This invention relates to machines for forming a blank of material into a plurality of sections and more particularly to the section forming means and a mechanism for adjusting the position of the section forming means in a manner so as to vary selectively the width of the sections.

In various types of blank forming machines wherein the blank is divided into side-by-side sections, the conventional construction requires that the section forming members be manually and individually adjusted. This manual adjustment is disadvantageous for many obvious reasons such, for example, as in the length of the downtime required to make the adjustment and the probability of human error in the spacing of the elements such that the sections are not of the desired width.

The problem of forming sections into selective widths of exact dimensions is of particular significance in the manufacture of paper board containers of rectangular cross section. conventionally, such containers are formed by cutting a continuous moving web into blank lengths of selective lengths and this blank is divided into four sections such that the blank is foldable into a closed rectangular container. To achieve the desired rectangular cross section of the box blank, it is essential that the sections of the blank forming the opposite sides of the container be of substantially equal width so that a true right angular relationship is obtained at each of the four corners. In the absence of a right angular relationship at the corners, the box loses some of its rigidity such that it tends to collapse.

In the formation of the blank for forming the paper board container, there is conventionally employed coacting pairs of slitting and scoring heads. These coacting scoring heads are typically mounted in a manner similar to that shown in one of the units of U.S. Patent No. 2,418,066 in which the pairs of coacting, slitting and slotting heads are mounted in spaced relation on shafts located above and below the moving blank. To readjust the distances between slitting and scoring heads, it is necessary to unloosen each of the heads carried on the shafts individually and thereafter slide the heads along the shafts to the desired spacing. As shown in the above mentioned patent, in order to decrease the down time of the machine while making the adjustments, there are employed two or more of slitting and scoring units of which at least one unit is in an active and operative position and the other is inactive. The desired adjustment changes are made on the inactive unit or units. While such arrangements are generally satisfactory, the additional units materially increase the overall cost of the machine. Furthermore, the adjustment of the spacing between the heads is dependent upon the accuracy of the operator such that oftentimes errors of spacing occur. As previously discussed, such errors of spacing result in a poor box structure.

It is an object of the present invention to provide a blank forming machine for forming four side-by-side sections with a novel arrangement for selectively and simultaneously varying the relative width of the sections in a manner such that the ratio of the sums of two adjacent sections to the sum of the two remaining adjacent sections remains constant.

It is a further object to provide a slitting and scoring apparatus for a paper box machine wherein the operating 3,093,037. Patented June 11, 1963 "ice parts are so constructed and arranged that the blank box dimensions may be varied without slowing down or stopping the feed of the paper web.

It is another object of the invention to provide a slitting and scoring apparatus for a paper board box machine having an improved arrangement for varying the spacing of the slitting and scoring heads such that the possibility of human error in making the adjustment is obviated whereby the width dimensional relationship of the sections formed by the scoring and slitting is retained to achieve a rectangular box.

It is still a further object of the invention to provide an adjusting mechanism for the slitting and scoring heads which is operative simultaneously and selectively to change the spacing between adjacent heads forming the opposite side sections of the box while at the same time, if it is so desired, maintaining the remaining two opposite side sections of the box at the same dimension.

In carrying out the invention for forming the blank into four side-by-side sections, there is employed a means for defining a datum line; means for defining a first section on one side of the datum line, means for defining a second section contiguous with said first section, means for defining a third section on the other side of said datum line; means for defining a fourth section contiguous with said third section and an adjustment means connecting said section defining means to selectively vary the distance of said means relative to said datum line so that the ratio of the sum of the first and second sections to the sum of the third and fourth sections remains constant.

Further objects and advantages of the invention will be in part obvious and in part specifically referred to in the description hereinafter contained which, taken in conjunction with the accompanying drawings discloses a preferred form of the apparatus constructed to operate in accordance with the invention. This disclosure, however, should be considered merely as illustrative of the principles of the invention in its broadest aspects.

In the drawings:

FIG. I is a fragmentary prospective view of the slotting and storing apparatus embodying the structure of the present invention.

FIG. 2 is a plan view of the lower heads of the slitting and scoring mechanism and the adjusting means employed in the present invention.

FIG. 3 is a view taken substantially along the lines III-III of FIG. 1 showing the mechanism for driving one of the screws for positioning one set of the slotting and scoring heads.

HO. 4 is a plan view of the blank.

Referring now to the drawing, the present invention is disclosed as it is embodied in the blank forming mechanism of a printer-slotter machine of the general type disclosed in the United States Patent No. 2,191,988. Such a machine generally comprises a means for sequentially feeding a rectangular sheet which has been previously cut to a preselected length to a printing arrangement not shown. Thereafter, the sheets are fed to a scoring and slotting mechanism 19 and 11, respectively, for forming the sheet into a blank K, which blank is adapted to be folded into a rectangular container.

As shown in FIGS. 1 and 2 the scoring mechanism 10 comprises an upper shaft 15a and a lower shaft 15b which are rotatably journaled on the frame 17 and driven by way of a main drive gear train not shown. Mounted for rotation with the shafts 15a and 15b are five pairs of coacting scoring heads 19a and 19b, 21a and 21b, 23a and 23b, 25a and 25b, and 27a and 27b. The coacting scoring heads are of conventional construction and serve J: to compress the paperboard sheet passing between the heads so as to provide a score line lengthwise of the sheet. The two outer coacting heads 19a and 19b, and 27a and 27b serve to define the outer limit of the blank to be formed while the remaining three are spaced along the shafts 15a and 15b so as to divide the sheet into four sections A, B, C, and D as shown in FIG. 4.

Spaced rearwardly of the scoring mechanism are shafts 29a and 29b of the slotting mechanism 11. Mounted on the shafts 29a and 2% are five pairs of coacting slotting heads 31a and 31b, 33a and 33b, 35a and 35b, 37a and 37b, and 39a and 39b. Each of the coacting slotting heads is arranged in running alignment with one of the scoring heads as shown. The outer slotting heads 31a and 31b are operative to sever one of the outer edges of the blank K while the outer heads 39a and 3% on the opposite side of the shaft 29a and 2% are operative to sever the opposite edge of the blank K and form a flap f. The flap f is employed to hold the box together in the well known manner. and 33b, and 35a and 35b, and 37a and 37b serve to form slots s of equal length in the leading and trailing edges of the sheet so that the resulting extensions between the slots s may later be folded over to form the bottom and top of a rectangular container.

Conventionally, each of the upper slotting heads 31a, 33a, 35a, 37a, and 39a mounted on the shaft 29a carry a knife blade or blades 41 and the lower heads 31b, 33b, 35b, 37b, and 39!) mounted on the shaft 2% are formed with peripheral recesses which receive the blades on the upper heads. The blades 41 on the upper heads are angularly adjustable such that in the event the rate of feed of the sheet or the sheet length is varied, or it is desired to change the length of the slot, the equal lengths of the slot may be maintained. The blade heads may be constructed to provide for such angular adjustment in accordance with any of the constructions known to the art.

As shown in FIG. 4 the blank K is arranged into four sections, A, B, C, and D of which the sections A and C are adapted to form opposite sides of a container are of equal width y and y. While the sections B and D are adapted to form the other two opposite sides of the container are also of equal width x and x. In connection with the widths y and x of the end sections A and D, under some circumstances it may be desirable to make one of these dimensions slightly less than the corresponding dimension x or 31' so that when the outer edges of the section A and D abut, the container to be folded from the blank forms a right angle at each of the four corners. This difference in width usually approximates the thickness of the paper board sheet.

In adjusting the spacing of the slotter and creaser heads on their respective shafts it is essential that the above width dimension relationship be maintained. In the event that there be an error of A of an inch for example in setting the heads defining the width dimension or and x of the sections B and D, the resulting box to be folded from the blank will be approximately /2 out of square. Hence, the resulting box will not be truly rectangular at the corners and will be subject to breakdown. It is evident, therefore, that a small error in the dimensional relationship of the opposite section widths is critical. In the manual adjustment of the heads as required heretofore, such errors are likely to occur especially where frequent changes in blank sizes are to be made.

In accordance with the present invention, these dimensional errors are prevented from occurring because the adjustment of the heads to change the size of the blank is accomplished in a manner that does not require individual and manual adjustment of the heads. To this end, the coacting scoring heads 23a and 23b and coacting slotting heads 35a and 35b aligned with the former are located intermediate of the shaft and 15a, and 29 and 29a, respectively. These heads are held against lengthwise movement of the shaft by suitable fastening The intermediate heads 33a means such as a set screw or the like. The remaining slotting heads 31a and 31b, 33a and 33b, 37a and 37b, and 39a and 39b and the aligned scoring heads 19a and 19b, 21a and 21b, 25a and 25b, and 27a and 27b are keyed to their respective shafts 29a and 29b, and 15a and 1512 by way of keys 43 extending along the shaft. In this manner these heads are movable lengthwise of the shafts and held for rotation therewith. Holding the longitudinally movable heads in a selective spaced relation along the lengths of the shafts is the adjustment means of the present invention generally designated as 45. As shown, the adjustment means 45 comprises an upper set of screws 47, 49, and 51 and an identical lower set of screws of 53, 55 and 57. The screws are suitably supported on the frame and for the purpose of clarity some of the supporting structure has been omitted from the drawings.

The screws 47 and 53 are provided with opposed threads on the ends 47 and 47", and 53' and 53" on each side of the datum line defined by the medium, aligned scoring head 35a and 35b, and 23a and 23b. That is as viewed in FIGS. 1 and 3 the ends of the screws 47' and 53' are formed with a right hand thread and the ends 47" and 53" are formed with a left hand thread.

The two screws 49 and 51 of the upper set and the two screws 55 and 57 of the lower set are each formed with the same hand thread which, as shown, is a right hand thread.

For conjointly moving the longitudinally aligned upper slotter and creaser heads 31a, 33a, 37a, 39a and 19a, 21a, 25a, 27a and the lower slotter and creaser heads and 31b, 33b, 37b, 39b, and 19b, 21b, 25b, 27b, there is provided a plurality of shifting members 59a, 61a, 63a and 65a for moving the upper set of heads and 59b, 61b, 63b, and 65b for moving the lower set of heads. The shifting arms are formed at each end with a yoke 67 having mounted in arms thereof free running balls 70 which engaged the sides of the slotting and creasing heads so that the latter are free to rotate.

The shifting members 59a and 59b, and 65a and 65b are threaded on the screw end 47' and 53' and 47" and 53", respectively by way of an internally threaded sleeve 66 fixed on the side of the shift members, and are provided with enlarged openings 72 to permit the free passage of the worms 49 and 51 and 55 and 57 therethrough. The intermediate shifting members 61a and 61b and 63a and 63b threaded on the worms 49, 55, 51, and 57, respectively by the sleeve 66 are provided with enlarged openings 72 similar to those provided in the arms of 59a and 59b, and 65a and 65b to permit the free passage of the worms 47 and 53 therethrough.

The above described arrangement is assembled such that the spacing of the slotter and creaser heads 33a and 33b, and 21a and 21b from the fixed mating slotter and creaser heads 35a and 35b, and 23a and 23b, respectively, is equal to the spacing of the mating slotter and creasing heads 37a and 37b, and 25a and 25b from the outer slotter and creaser heads 39a and 39b, and 27a and 27b, respectively. That is, as shown, distance x equals 1:. The outer mating slotter and creaser heads 31a and 31b, and 19a and 19!) are spaced from the slotter and creaser heads 33a and 33b, and 21a and 21b, respectively, an amount equal to the spacing of 37a and 37b, and 25a and 25b from the fixed slotter and creaser heads 35a and 35b and 23a and 23b, respectively. That is, as shown, the distance y equals the distance y.

In the event the circumstances are such that either of the end sections A or D are to be made of a lesser dimension than its corresponding opposite side B or C, provision therefore may readily be made during the assembly of the device.

It is to be noted that the heads are arranged such that the sum of the distances and x on one side of the fixed heads 35a, 35b, 23a, 23b is equal to the sum of the distances of y and x. This relationship of the heads may also be expressed in the terms of the ratio of the sums of the distances y and x to the sum of the distances y and x. When so expressed the above described arrangement results in a substantially ll ratio. However, when the present invention is embodied in machines other than a printer slotter, the section defining means corresponding to the creaser and slotter heads may be arranged such that the sum of the distances y and x and y and x are not equal. Under these conditions a ratio other than unity would be obtained.

As more fully to be demonstrated hereafter when anyone of the dimensions on one side of the fixed heads is changed the adjusting arrangement of the present invention is operative to vary the other dimensions such that the original ratio of the sums of the distances be tween the movable heads on one side of the fixed heads to the sum of the distances between the movable heads on the other side of the fixed heads is retained.

To selectively vary the y and y dimensions there is provided a reversible induction motor 68 which drives shaft 69 on which there is fastened a spur gear 71. The first drive gear 71 meshes with a gear 73 fast on the end of a hub 75 rotatably journaled on a shaft 76 of a differential gearing arrangement 77. The shaft 76 is suitably mounted on the frame member 17. Formed on one end of the hub 75 is a bevel gear 74 which meshes with a bevel sun gear 79 rotatably journaled on the upper end of a shaft 81. The lower end of the shaft 81 is fixed by a collar 83 to a shaft 76 by way of any suitable fastening means such as a set screw or the like. The differential arrangement 77 also includes a beveled gear 85 carried on the end of a hub 87 journaled for rotation about the shaft 76. A gear 91 fixed to the end of the hub 87 and rotatable therewith meshes with a second driving gear 93 fixed to a shaft 95 driven by a reversible inductive motor 97.

Fast to the shaft 76 adjacent the frame 17 is a gear 99 meshing with a pinion gear 101 fixed to the end of the screw 47.

To drive the screw 53 simultaneously with the screw 47 there is provided an idler gear 103 which meshes with a gear 105 fixed to the end of the screw 53.

To drive the screw member 51 and the screw member 57 on the other side of the fixed head 35a, 35b, 23a and 23b there is carried on the far end of the shaft 69 a pulley 107 which drives by way of belt 110 a double sheave pulley 112 fixed to the end of screw 51. As shown in FIG. 3 a belt 114 drives a pulley 115 fixed to the end of screw 57.

In operation the motor 68 is energized so as to rotate in the direction to either increase or decrease the y, or y. Energization of the motor causes the shaft 69 to rotate so that the driving gear 71 in meshing engagement with the gear 73 causes the bevel gear of 74 of the differential arrangement 77 to rotate about the shaft 76. The bevel gear 74 in meshing engagement with the sun gear 79 turns the latter about the two bevel gears 85 and 74; the bevel gear 85 being held stationary since the motor 97 is inoperative and holds the gears 93 and 91 fixed. Turning of the sun gear 79 rotates the shaft 76 and the gear 99 fixed on the end thereof. The gear 99 which is in meshing engagement with the gear 101 fixed on the end of the screw 47 and the idler gear 103 drives the gear 105 fixed on the screw 53 so as to turn the screws 47 and 53.

Assuming that the motor 68 is energized to increase the y and y distance, turning of the screws 47 and 53 causes the shifting arms 59a and which are threaded on the ends 47' and 53 to move to the left, and the arms 65a and 65b threaded on the end 47" and 53" to move to the right.

in this manner the distances of the heads 39a, 39b, 27a and 27b on one side and the heads 31a, 31b, 19a and 19b on the other side of the fixed heads 35a, 35b, 23 and 23b are maintained equally spaced from these fixed heads. The yoked ends of the shifting arms 59a and 59b, and 65a and 65b in engagement, respectively, with the slotting heads 31a and 31b and scoring heads 19a and 19b, and heads 39a and 39b, and 27a and 27b move the latter a corresponding distance. In connection with the distance that the heads are moved, suitable indicia means may be provided on or adjacent the slotting and scoring shafts 15a and 290 respectively so that when the heads have been moved to the desired spacing, the motor 68 is deenergized.

To move the slotting heads 37a and 37b and scoring heads 25a and 25b the same distance as the scoring heads and slotting heads 19a and 19b, and 31a and 31b and thereby maintain the y and y distances equal, the shifting arm 63a and 63b threaded on the screws 51 and 57 and engaging the slotting heads 37a and 37b and scoring heads 25a and 25b are moved to the right. Such movement is accomplished by the arrangement of pulley 107, belt 110, pulley 112, belt 114, and pulley 115, previously described. It is to be observed that this movement of the heads is such that the x distance equals the 2: distance and these two dimensions remain unchanged.

To vary the x and x dimensions while maintaining the y and y dimension constant, the motor 97 is energized. Energization of the motor 97 rotates the shaft 95 and the screw 49 coupled to the former by a coupling sleeve 98. A gear 109 fixed to the screw 49 drives an idler gear 111 which meshes with a gear 113 fixed to the end of the screw 55 and rotates the latter. Rotation of the screw 49 moves the shifting arm 61a and rotation of the screw 55 moves the shifting arm 611;. With the arrangement shown the movement of the arms 61a and 61b is simultaneous such that the coacting scoring heads 33a and 33b, and 21a and 21b are simultaneously moved relative to the fixed slotting and scoring heads 35a and 35b, and 23a and 23b. Assuming it is desired to increase the x and x dimension without changing the y and y dimensions, the motor 97 is energized to rotate the screws 49 and 55 so as to move the shifting arms 61a and 61b and the heads 33a, 33b, 21a and 21b away from the fixed heads 35a and 35b, and 23a and 23b. When the heads have been moved the desired distance x, the motor 97 is deenergized.

Concurrently with the movement of the shifting arms 61a and 61b, the drive gear 93 mounted adjacent the motor drives the gear 91 of the differential mechanism 77. Rotation of the gear 91 causes the bevel gear 85 mounted for rotation about the shaft to rotate such that the sun gear turns about the two gears 85 and 74; the bevel gear 74 is stationary since the motor 68 is not energized. Rotation of the sun gear which is fast by way of the collar 81 to the shaft 76 causes the latter to rotate and thereby also turns the gear 99 and the gear 101 meshing therewithto rotate and turn the screw 47. The idler gear 103 meshing with the gear 105, fast on screw 53 turns the latter. Turning of the screws 47 and 53 causes the shifting arms 59a and 59b threaded on the ends 47' and 53 respectively to move to the left and the arms 65:: and 65b threaded on the ends 47" and 53" to move in the opposite direction such that the heads 29a, 29b, 19a: and 19b and heads 39a, 39b, 27a and 27b are moved a distance corresponding to the distance heads 33a, 33b, 21a and 21b have been moved from the stationary heads. It is to be noted that the heads 37a, 37b, 25a and 25b remain stationary such that the y distance remains constant and only the x distance is changed such that it equals the distance x. Also, the movement of the heads 31a, 31b, 19a and 19b corresponds to the distance that the heads 33a, 33b, 21a and 21b have been moved such that the should be readily apparent. The spacing of co-acting pairs of slotting heads and co-acting pairs of scoring heads are simultaneously adjustable while the machine is running so that the production of paperboard boxes, when the invention is employed therewith, is materially increased. Furthermore the adjustments and change of head locations are made in such a manner that the precise dimensional relationship is always maintained.

What is claimed is:

1. A machine for forming a blank into sections comprising means for defining a datum line, means for defining a first section adjacent one side of said datum line, means for defining a second section adjacent said first section, means for defining a third section adjacent the other side of said datum line, means for defining a fourth section adjacent said third section, and means interconnecting said section defining means for simultaneously repositioning a plurality of said section defining means to a selected extent relative to said datum line so that the ratio of the sum of the widths of said first and second sections to the sum of the widths of said third and fourth sections remains constant.

2. A machine for forming a blank into sections comprising means for defining a datum line, means for defining a first section adjacent one side of said datum line, means for defining a second section adjacent said first section, means for defining a third section adjacent the other side of said datum line, means for defining a fourth section adjacent said third section, and means interconnecting said section defining means for selectively varying the distance of one of said section defining means from said datum line and simultaneously therewith varying the distances of each of two of the other of said section defining means from said datum line so that the ratio of the sum of said first and second sections to the sum of said third and fourth sections remains equal.

3. A machine for forming an advancing sheet into sections comprising means for defining a datum line substantially intermediate the width of said sheet, means for defining a first section of predetermined width one side of said datum line, means for defining a second section of predetermined width adjacent said first section, means for defining a third section adjacent the other side of said datum line said third section having a width substantially equal to the width of said second section, means for defining a fourth section adjacent said third section defining means said fourth section having a width substantially equal to the width of said first section, and means interconnecting said section defining means for selectively repositioning a plurality of said section defining means relative to said datum line so that the sum of the predetermined widths of said first and second sections remains equal to the sum of the predetermined widths of said third and fourth sections.

4. A machine for forming an advancing sheet into sections comprising means for defining a datum line substantially intermediate the Width of said sheet, means defining a first section of predetermined width adjacent one side of said datum line, means for defining a second section of predetermined width adjacent said first section, means for defining a third section on the other side of said datum line, said third section having a width substantially equal to the Width of said second section, means for defining a fourth section adjacent said third section, said fourth section having a width substantially equal to the width of said first section, and means interconnecting said section defining means for selectively varying the width of one of said sections on one side of said datum line and simultaneously varying the widths of the sections on the other side of said datum line a corresponding amount so that the ratio of the sum of the widths of the first and second sections to the sum of the widths of the third and fourth sections remains unchanged.

5. A machine for forming an advancing sheet into sections comprising a rotatable shaft, a plurality of section forming heads spaced lengthwise of said shaft and mounted for rotation therewith, one of said heads being fixed on said shaft against movement relative thereto, means mounting the others of said heads for lengthwise movement of said shaft relative to said one head, said lengthwise movable heads being positioned on said shafts to define two sections on said sheet on each side of said fixed head, and means interconnecting said heads for selectively varying the width of one of said sections on one side of said one head and simultaneously varying the widths of the sections on the opposite side of said one head a corresponding amount so that the ratio of the sum of the widths of the two sections on one side of said head to the sum of the widths of the two sections on the opposite side thereof remains constant.

6. A machine for forming an advancing sheet into sections comprising a rotatable shaft, a plurality of section forming heads spaced lengthwise of said shaft and mounted for rotation therewith, one of said heads being fixed on said shaft against movement relative thereto, means mounting the others of said heads for movement lengthwise of said shaft relative to said one head, said lengthwise movable heads being positioned on said shaft to defines two sections on said sheet on each side of said one head, a first screw means connecting the outermost movable head to each side of said one head for moving said heads in opposite directions relative to said one head, a second screw means for moving a movable head located intermediate one of said outermost movable heads and said one head, a third screw means for moving a movable head located intermediate the other of said outermost heads and said one head, and means for conjointly rotating said screws so as to vary selectively the spacing between said heads and maintain constant the ratio of the sum of the distances between the movable heads on one side of said one head to the sum of the distances between the movable heads on the opposite side thereof.

7. In a scoring and slotter machine comprising a frame, a first pair of parallel shafts rotatably journaled in said frame, a second pair of parallel shafts spaced from and parallel to said first pair of shafts and rotatably journaled in said frame, a plurality of coacting slotting heads mounted on said first pair of shafts for rotation therewith, a plurality of coacting scoring heads mounted on said second pair of shafts of rotation therewith and disposed such that each pair of said coacting scoring heads is aligned with one of each of said pairs of slotting heads so as to provide aligned sets of coacting slotting and coacting scoring heads, one of said sets of coacting heads being fixed on said shafts against movement relative thereto, and means mounting the others of said sets of coacting heads for movement lengthwise of said shafts relative to said fixed set, said lengthwise movable sets of heads being spaced on said shafts to define two sections on each side of said set of fixed heads, and means interconnecting each of said movable sets of heads for varying the width of one of the sections on one side of said fixed set of heads and simultaneously varying the spacing of the sections on the opposite side of said set of fixed heads a corresponding amount so that the ratio of the sum of the widths of the two sections on one side of the set of fixed heads to the sum of the widths of the two sections on the opposite side thereof remains constant.

8. In a scoring and slotter machine comprising a frame, a first pair of parallel shafts rotatably journaled in said frame, a second pair of parallel shafts spaced from and parallel to said first pair of shafts and rotatably journaled in said frame, a plurality of coacting slotting heads mounted on said first pair of shafts for rotation therewith, a plurality of coacting scoring heads mounted on said second pair of shafts for rotation therewith and disposed such that each pair of said coacting scoring heads is aligned with one of each of said pairs of slotting heads so as to provide aligned sets of coacting slotting and coacting scoring heads, one of said sets of coacting heads being fixed on said shafts against movement relative thereto, and means mounting the others of said sets of coacting heads for movement lengthwise of said shafts relative to said fixed set, said lengthwise movable sets of heads being spaced on said shafts to define two sections on each side of said set of fixed heads, a first set of screw means connecting the outermost set to each side of said set of fixed heads for moving said outermost sets of heads in opposite directions relative to said set of fixed heads, a second set of screw means for moving a set of heads intermediate one of said outermost sets of heads and said set of fixed heads, a third set of screws 15 2,982,189

for moving a set of heads intermediate the other of said outermost sets of heads and said set of fixed heads, and means for conjointly driving said screws so as to vary selectively the spacing between said sets of heads and maintain constant the ratio of the sum of the spacings between the sets of heads on one side of said set of fixed heads to the sum of the spacings between the movable heads on the opposite side thereof.

References Cited in the file of this patent UNITED STATES PATENTS Swift .1 Oct. 23, 1934 Mueller Mar. 23, 1944 Shields May 2, 1961 

1. A MACHINE FOR FORMING A BLANK INTO SECTIONS COMPRISING MEANS FOR DEFINING A DATUM LINE, MEANS FOR DEFINING A FIRST SECTION ADJACENT ONE SIDE OF SAID DATUM LINE, MEANS FOR DEFINING A SECOND SECTION ADJACENT SAID FIRST SECTION, MEANS FOR DEFINING A THIRD SECTION ADJACENT THE OTHER SIDE OF SAID DATUM LINE, MEANS FOR DEFINING A FOURTH SECTION ADJACENT SAID THIRD SECTION, AND MEANS INTERCONNECTING SAID SECTION DEFINING MEANS FOR SIMULTANEOUSLY REPOSITIONING A PLURALITY OF SAID SECTION DEFINING MEANS TO A SELECTED EXTENT RELATIVE TO SAID DATUM LINE SO THAT THE RATIO OF THE SUM OF THE WIDTHS OF SAID FIRST AND SECOND SECTIONS TO THE SUM OF THE WIDTHS OF SAID THIRD AND FOURTH SECTIONS REMAINS CONSTANT. 